458 
SECTION FROM YERCH- URALSK TO STERLITAMAK. 
the belief, that the masses, which here afforded us true evidences of their age, were 
probably the mere northern prolongations of those monotonous and subcrystalline 
rocks of the great plateau of the Sakmara, amid which we had detected no vestiges 
of them. 
These Silurian quartz rocks proceeding from the range of the Iremel seemed to 
fold over and form a sort of axis, and to the west they are followed by slates having 
the most marked slaty cleavage which we had seen in the Ural chain 1 . The system 
of schists and black limestone is thence continued in undulations, one peak of quartz 
rock only, the Yuluch-gora, appearing on the banks of the Bielaya, just where that 
river turns to the south, and flows to the Zavod of Uziansk 2 , — a grand and pictu- 
resque position, with high calcareous banks. 
Again, schists, quartzose bands and limestone are thrown about in undulations 
producing a lovely and rich country, extending from the Uziansk to the Zavod of 
Avziansk, but as in this space the road following the river Bielaya to the south, runs 
chiefly in the direction of the chain, we could not look for much variation. In 
approaching Avziansk, however, we again traversed to the west by a rocky defile, 
which clearly explains, how much the country is made up of repetitions of a great 
series of sedimentary rocks. On the eastern bank of the stream a large mass of 
thick-bedded limestone dips sharply to the east, whilst on the other, slaty lime- 
stones with calcareous schists, &c. plunge still more rapidly (70°) to the west. The 
limestones are overlaid by calcareous grits and schists, and the latter by flagstones, 
and grey, purple and whitish grits, with a basis of felspar ; in parts almost a quartz 
rock. These strata occupy a distinct basin of about a mile or more in breadth, from 
the western side of which limestones, containing concretions of silex, rise up with 
a rapid inclination to the east. Though we employed our hammers for some time, 
and traversed the sides and summits of this little basin on foot, we were to our 
great mortification unable to detect in it any fossils, yet, doubtless, such may 
be found by persons who have time at their command. Whilst they were un- 
questionably, from their mineral character, members of the palaeozoic series (for 
they had not a feature of crystalline or primarized rocks), we were unable, in the 
1 These slates, the laminae of which marked by different colours are crossed by cleavage planes, occur 
about four versts east of the floating bridge of Perevosnia. 
2 This Zavod of Uziansk belongs to M. J. Demidoff, in the deep-coloured limestones of which we found 
the Favosites polymorpha and large Cyathophyllum, very nearly allied to the C. diantkus. These rocks 
may, therefore, be either Devonian or Silurian. 
